Many optical devices, such as microdisplays in electronic cameras and other types of display system, require illumination by a beam of light having relatively uniform brightness. Generally, light sources, such as incandescent lights, arc lamps, and light emitting diodes, provide a nonuniform light output that is unsuitable for direct use, so the light is typically homogenized in a diffusing cavity before illuminating a display unit. The display unit is often a reflective display unit, for example a reflective liquid crystal display panel, an array of tunable mirrors or “electronic paper”. A polarization sensitive mirror is often used to direct light from the light source to the display unit.
The light source and display unit are typically mounted separately from each other on the display system housing, and are electrically connected via flex circuitry. This approach results in high component and fabrication costs, and a fault in the flex circuitry or in the connectors is often a primary failure mechanism for the display system.
Therefore, there is a need for a display system that is less expensive to fabricate and is more reliable than current display systems.